By doing some research on the aw site i came up with the following thanks to aw:
For the Area51-m:
To achieve its incredible performace this computer uses a desktop processor, which lowers battery life. The time the battery lasts depends on how the system is being used. Check the examples below:
Normal load (Email - browsing - word processing): 2:00 hours.
Full load (DVD playback, gaming): 1:30 to 1:45 hours.
For the Sentia:
This computer is based on Intel's newest mobile chipset, the Centrino. This chipset has advanced power management capabilities that allow it to conserve battery life by lowering the system's power consumption.
With 1 battery: 3:30 to 4:00 hours.
With Auxiliary battery: 5:30 to 6:00 hours.
Please keep in mind the times shown are approximate and may vary.